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Investments - Future payments under contractual commitments (Details) $ in Millions | Dec. 31, 2020 CAD ($)
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Disclosure of subsidiaries [line items] |
Long-term service agreements | $ 173
SP Skookumchuck Investment, LLC |
Disclosure of subsidiaries [line items] |
Long-term service agreements | 33
2021 |
Disclosure of subsidiaries [line items] |
Long-term service agreements | 31
2021 | SP Skookumchuck Investment, LLC |
Disclosure of subsidiaries [line items] |
Long-term service agreements | 1
2022 |
Disclosure of subsidiaries [line items] |
Long-term service agreements | 37
2022 | SP Skookumchuck Investment, LLC |
Disclosure of subsidiaries [line items] |
Long-term service agreements | 1
2023 |
Disclosure of subsidiaries [line items] |
Long-term service agreements | 22
2023 | SP Skookumchuck Investment, LLC |
Disclosure of subsidiaries [line items] |
Long-term service agreements | 1
2024 |
Disclosure of subsidiaries [line items] |
Long-term service agreements | 18
2024 | SP Skookumchuck Investment, LLC |
Disclosure of subsidiaries [line items] |
Long-term service agreements | 1
2025 |
Disclosure of subsidiaries [line items] |
Long-term service agreements | 10
2025 | SP Skookumchuck Investment, LLC |
Disclosure of subsidiaries [line items] |
Long-term service agreements | 1
2026 |
Disclosure of subsidiaries [line items] |
Long-term service agreements | 55
2026 | SP Skookumchuck Investment, LLC |
Disclosure of subsidiaries [line items] |
Long-term service agreements | $ 28

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